The muscular dystrophies are the heterogeneous group of inherited muscular disorders characterized by muscle wasting and weakness, and are affecting both children and adults. The worldwide prevalence of inherited neuromuscular diseases estimated in a review study was of 28.6/100,000 and 33.3/100,000 if rarer disorders are included. As a group, these disorders, covers a considerable proportion of patients with chronic disease, however, recent studies of prevalence of the muscular dystrophies in the United States are lacking. This project will conduct population-based surveillance and longitudinal follow-up of individuals with muscular dystrophies and neuromuscular disorders using the methods from the Muscular Dystrophy surveillance Tracking and Research Network (MDSTARnet). This will be used for public health research to examine prevalence, survival, health care services and disparities in care.